Previous studies show that hypogonadism is associated with a higher incidence of type 2 diabetes in male patients, in contrast, hyperandrogenism is associated with higher risk of type 2 diabetes in women. We hypothesized that there androgens may have negative effects on beta-cell functions. Androgen receptors may be important for function of beta cells. Androgen replacement may increase beta cell dysfunction and antiandrogen treatment may restore beta cell dysfunction in patients with polycystic ovary syndrome (PCOS). Also androgen receptors may be new era for Islet Cell transplantation. Researches in patients with PCOS and hypogonadism are necessary to test this hypothesis.